Cold stamping and hot stamping are both types of stamping. Stamping relies on presses and molds to plastically deform or separate plates, strips, pipes, etc., thereby obtaining the required formed parts.
Cold stamping refers to metal parts processing at room temperature. Generally, the material thickness is <4mm. The advantages of cold stamping are - no need for heating, no oxide scale, good surface quality, easy operation, and low cost; the disadvantage is that work hardening will occur, and in severe cases, the metal will lose its ability to further deform.
Cold stamping requires a uniform thickness of the blank with a small fluctuation range, a smooth surface, no spots, and no scratches.
Hot stamping is a stamping processing method that heats metal to a certain temperature range. The thickness of the sheet is required to be above 8-10mm, and it needs to be stamped after heating.
The benefits of hot stamping are as follows:
1-Compared with cold stamping, hot stamping has better formability;
2-The dimensional accuracy is good. The strength of cold stamping parts is only about 600MPa, and there is obvious rebound. The strength of hot stamping parts is about 1500MPa, and there is almost no rebound.
3-The surface hardness, dent resistance and stiffness of the parts are relatively good;
4-For automotive stamping parts, ultra-high-strength body parts can be obtained, which can thin the thickness of the parts, reduce the number of body reinforcement plates, improve the collision performance of the body, and achieve effective weight reduction of the body. This has led to the widespread adoption of thermoforming technology in the automotive industry.
The above advantages are not enough to prove that hot stamping has no disadvantages. Hot stamping also has obvious shortcomings. For example, the manufacturing cost of hot stamping parts is high, the mold price is high, the energy consumption is large, and laser cutting is required, so the cost is much higher than that of cold stamping; the production and processing process is relatively slow;
It can be seen from the above that hot stamping is mainly used in the field of automobile processing and manufacturing; but cold stamping molds have relatively more industrial applications, such as automobiles, electronics, home appliances, aviation and other fields. Taking the field of automobile processing as an example, cold stamping is widely used in the manufacture of body parts, doors, seats and other parts; while in the field of electronic products, cold stamping is widely used in computer & host casings;
In general, stamping technology is a mature method that relies on presses and molds to apply external forces to various materials (plates, strips, pipes, profiles, etc.), causing these materials to produce plasticity under the action of external forces, thereby deforming or separating. The molding processing method thus obtains the desired shape and size. Stamping technology includes many forms, the most commonly used of which are cold stamping and hot stamping, bending, flanging, etc.